1. Field
The present disclosure relates generally to electrosurgical system and method, more specifically, to a system and method for closed loop monitoring of monopolar electrosurgical apparatus to sense tissue and energy properties and control energy delivery based on the sensed properties.
2. Description of the Related Art
Electrosurgery involves application of high radio frequency electrical current to a surgical site to cut, ablate, or coagulate tissue. In monopolar electrosurgery, a source or active electrode delivers radio frequency energy from the electrosurgical generator to the tissue and a return electrode carries the current back to the generator. In monopolar electrosurgery, the source electrode is typically part of the surgical instrument held by the surgeon and applied to the tissue to be treated. A patient return electrode is placed remotely from the active electrode to carry the current back to the generator.
In bipolar electrosurgery, one of the electrodes of the hand-held instrument functions as the active electrode and the other as the return electrode. The return electrode is placed in close proximity to the active (current supplying) electrode such that an electrical circuit is formed between the two electrodes. Commonly, electrodes in bipolar electrosurgical systems are disposed within electrosurgical forceps, which lend itself particularly well to vessel sealing. In this manner, the applied electrical current is limited to the body tissue positioned between the electrodes. When the electrodes are sufficiently separated from one another, the electrical circuit is open and thus inadvertent contact of body tissue with either of the separated electrodes does not cause current to flow.
Electrosurgical generators are capable of producing a variety of electrical waveforms. Certain waveforms are better suited for specific electrosurgical procedures. A continuous waveform having a duty cycle of 100% is best suited for cutting the tissue since the energy produces heat very rapidly thereby vaporizing the tissue. An intermittent waveform, where the duty cycle of about 10% is best suited for coagulating the tissue since the amount of heat generated is reduced.
Currently parameters affecting the coagulation waveform are adjusted manually by the surgeon. This adjustment process is cumbersome since the coagulation waveform may need to be adjusted continuously during its delivery. However, there are no systems available which can adjust the coagulation waveform automatically.